ML16342A137
| ML16342A137 | |
| Person / Time | |
|---|---|
| Site: | Diablo Canyon  |
| Issue date: | 05/25/1993 |
| From: | Coblentz L, Reese J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| To: | |
| Shared Package | |
| ML16342A136 | List: |
| References | |
| 50-275-93-14, 50-323-93-14, EA-93-107, NUDOCS 9306220237 | |
| Download: ML16342A137 (76) | |
See also: IR 05000275/1993014
Text
EA No.:
Report:
Dockets:
Licenses:
U. S.
NUCLEAR REGULATORY COMMISSION
REGION
V
93-107
50-275/93-14
and 50-323/93-14
50-275
and 50-323
DPR-80 and OPR-82
Licensee:
Faci 1 ity:
Pacific Gas
and Electric Company
(PGImE)
77 Beale Street,
Room
1451
San Francisco,
94106
Diablo Canyon
Power Plant
Meeting Location:
Region
V Office, Walnut Creek, California
Meeting Date:
Prepared
By:
May 19
1993
L.
ntz,
Seni
Approved By:
~Summa':
J
me
. Reese,
Chief
ili ies Radiologi
l Protection
Branch
F-zs 8
Date Signed
Areas
Reviewed:
Previously announced
enforcement
conference,
held at the
request of NRC Region
V, to discuss
the licensee's
analysis of several
apparent violations of NRC requirements
related to post-accident
sampling
and
analysis,
as presented
in
NRC Inspection
Report 50-275/93-1)
and 50-323/93-11.
Results:
The licensee
presented its analyses
of the apparent violations,
including
a discussion of the root causes,
corrective actions
taken,
additional corrective actions
proposed,
and overall safety significance.
Fo~
a copy of the licensee's
presentation,
see Attachment
A to this report,
The licensee's
presentati on demonstrated
an understanding
of the i ssues
involved.
Corrective actions
presented
were thorough
and technically sound.
No additional violations of NPC requirements
were identified.
930b220237
930525
ADOCK 05000275
6
DETAILS
Persons
Attendin
Licensee
J.
Boots, Director, Chemistry
W. Fujimoto, Vice President,
Nuclear Technical
Services
J.
Gardner,
Senior Engineer,
Chemistry
T. Greble, Supervisor,
Regulatory
Compliance
T. Hack, Senior Engineer,
Radiological Analysis
D. Hiklush, Manager,
Operations
Services
J. Holden, Director, Instrumentation
and Control
R. Powers,
Manager,
Nuclear guality Services
G. Rueger,
Senior Vice President,
Nuclear Power Generation
J. Sexton,
Manager, guality Assurance
J. Shiffer, Executive Vice President-
J.
Tomkins, Director, Nuclear Regulatory Affairs
C. Warner,
Law Department
NRC
K. Brewer, Radiation Specialist
H. Chancy,
Senior Radiation Specialist
L. Coblentz,
Senior
Radiation Specialist
B. Faulkenberry,
Deputy Regional Administrator
R. Huey, Regional
Enforcement Officer
K. Perkins, Director, Division of Reactor Safety
and Projects
(DRSP)
S. Peterson,
Project Manager,
J.
Reese,
Chief, Facilities'adiological
Protection
Branch
S. Richards,
Deputy Director,
DRSP
R. Scarano,
Director, Division of Radiation Safety
and Safeguards
(DRSS)
F. Wenslawski,
Deputy Director,
DRSS
Enforcement
Conference
Overview
The individuals listed in Section
1, above,
met on Hay 19,
1993,
to
discuss
the licensee's
analysis of post-accident
samp'ling issues
rais
d
in
NRC Inspection
Peport
50-275/93-11
and 50-323/93-11.
Hr. B. Faulkenberry
opened
the meeting <<'ith a discussion of the meeting
format and introduction of the general
meeting topics.
fI> . J. Shiffe',
responded
with an overview of the
PGE:E reaction to the
NRC i nspection
issues
raised.
Hr. J.
Reese
then outlined the apparent violations to be discussed.
These
included:
{1) the fai lure to implement
and maintain
a program,
as
required
by Technical Specification
{TS) 6.8.4, that <<ould ensure
the
capability to obtain -nd analyze
samples of radioiodines
and particulat=s
in plant gaseous
effluents
under accident conditions;
(2) the failure t.
implement
and maintain
a program,
as required
by TS 6.8.:; that wo'd
- -.nsure the capability to obtain
and analyze
sa;-:.~les of reactc',
cool=-:~'
Pi (zsl zrpp',
j >t v
zww
<s~p
si imp> pe>
tv pp',, z r>',.
~
~;f<
Iw
~
vl
i 1'd
l
4
~ 4<" 'lail Cl
e'4
~"Etsvik
~~,->w>L ~ ~
I
~
perform
a written safety evaluation,
as required
by 10 CFR 50.59, for
changes
made to the post-accident
sampling system.
Hr.
G. Rueger introduced
PGKE's presentation
of the apparent violations.
Hr. Rueger noted that each of the problems
had occurred during efforts to
upgrade post-accident
monitoring capabilities,
and reaffirmed PG8E's
overall intention to maintain
a strong post-accident
samp'ling
and
analysis
program.
The meeting progressed
to a detailed discussion of each of the -apparent
violations.
For each
one,
the licensee
presented its general
agreement
or disagreement
'as to whether
a requirement
had been violated, the root
cause
or causes,
the corrective actions
taken,
and the correcti ve acti ons
proposed.
Hr. Rueger,
Hr. J.
Gardner,
Hr. J.
Boots, Hr. J. Holden,
and
Hr. D. Hiklush presented
the licensee's
analyses
of the issues.
guestions
and additional
information were presented
by various
members of
the
NRC and
PGKE staff.
The
NRC Enforcement Policy was summarized
as it
related to the inspection findings.
The licensee's
handout
and slides,
used
as the outline for the overall
discussion,
are presented
as Attachment
A to this report.
Several
specific points of discussion
are presented
in Section
3, below.
At the conclusion of the meeting,
Hr. Shiffer summarized
the licensee's
commitment to ensuring
an effective program for post-accident
sampling
as
well as effective oversight of changes
to that program.
Hr. Faulkenberry
closed the meeting
by acknowledging Hr. Shiffer's
and others'emarks
and
thanki ng the licensee for its presentation
efforts.
3.
S ecific Points of Discussion
In the course of the licensee's
presentation,
several
points received
particular attention
and discussion:
Overall Safet
Si nificance
The licensee
noted several
points related to actual
safety
significance of the apparent violations.
Regarding reactor coolant
dissolved
hydrogen quantification,
the licensee
noted that little
dependence
was placed
on this parameter
in assessment
of post-
accident conditions.
Other more effective and dependable
methods
were available for core
damage
assessment,
and for d termining th
presence
of a hydrogen
bubb'le in the reactor vessel.
Regarding
the plant vent iodine and particulate monitor, the
licensee
noted that the high-range monitor,
R>:-40,
was onl'y 'used
i',:
worst-case
conditions, for accidents
beyond the Final Safety
Analy is Report design basis.
The license
also noted that,
even
fol
wol st-case
accid=-nt conditions,
the pla;,t vent high-range
c'ice"
g
m-. a monitor,
RE-29, could be used to e,,tr-polate
.-"
the emergency
procedures'.
Protective action recommendations,
would
be conservatively
based
on plant conditions rather than
on RX-40 or
other sample results.
b.
Monitor Out-of-Service
Time
The licensee
acknowledged that RX-40 had
been unavailable
from
February
26 to March 9,
1993,
as noted in the inspection report.
The licensee
emphasized,
however, that no "limiting condition for
operation" or other criteria specified the allowable length of time
that RX-40 could be out of service.
Based
on -the overall
use of the
monitor, the available alternate
means of making similar
assessments,
and specifications
for similar types of monitors,
the
licensee
stated that having the monitor out of service for 12 days
seemed
reasonable.
The licensee
acknowledged,
however, that Equipment Control Guideline
(ECG)
11. 1, which administratively controls actions
to be taken
when
post-accident
moni toring equipment is out of service,
gave
no
guidelines for how long RX-40 could be out of service.
The licensee
noted that the
ECG was in error in designating
RE-32 (the mid-range
monitor)
as the primary monitor, in the sense that RE-32 could not
meet the licensee's
commitment to NUREG-0737.
The licensee
stated
that,
given these
problems with
ECG 11. 1, the program would have
relied
on supervisory oversight to ensure that RX-40 was returned to
service in a timely fashion.
4.
Corrections
to
NRC Ins ection
Re ort 50-275 93-11
and
50-323
93-11
No errors
were noted in the i nspection report.
1. I
~
-NFORCEMENT CONFERENCE
MAY 19,
I 993
~NALNUT CREEK,
CA
NRC /SSVES
Plant
veni radioiodine
and
particulates
BX-40 out of service
for
32
days
w!ithout a GDC-19
backup
i3eactoi
coolant
(RC) dissolved
Low availability of Unit
2 in-line monitor
No
I 0
CFR 60.69
for gas
chromatograph
(GC)
bacl'up
deletion
After 'GC deletion,
backup
methods
did not
meet
GDC-19 requirement
IMQIOIOOINEANO PARTICULATES ANALYSIS
OVERVIEW
Actual outage
time for RX-40 was
reasonable
Equipmeni
controi guidelines
did not accurately
reflect primary
and
backup
equipment
designation
Digital radiation
monitoring system
(DBMS) upgrade
and
procedural
corrective
actions
have
already
been
implemented
Safety
significance
very low
PC QISSOI l!ED HYOROGEN ANALYSIS
OVERVIEW
No backup
requirements
existed
prior to
1990
wh".=n in-line 'monitor was
installed
initially, the in-line monitor configuration
did
have
backup.
GDC-19 requirements
were
not met,
however,
from
1 992
on when
the
GC backup
vJ as
cl Is c 0 n t(nu e d.
GC backup
method
should
not have
been
discontinued
i~ 1992
v~ithout
a written safety
evaluation
Though
Unit 9 in-line monitor has
had
Low
availability since
mid-3992,
maintenance
was
diligently pursued
throughout
the period
Timely and
comprehensive
corrective
actions
have
b
- en
taken
Safety
significance
very:low
II
~
~ ~ ~ ~
HADIQIQDI¹S AND PARTICULATES ANALYSIS
NRC ISSUE
T.S.
6.8.4
was
not
met
because
the
plant vent
high
range.
sampler
for radioiodines
and
particulates
(RX-40)
vistas
removed
from service
for
12 days
vflthout a GDC- 3 9 backup
RADIOIODINES AND PARTICULATES
TI=CI IN-ICAL SPECIFICATION REQUIREMENTS
Bequif Bs the licensee. to establish,
implement
and
maintain'
program
which will ensure
the
capability
to obtain
and
analyze
radioactive
and
particulates
in plant gaseous
effluen'is
under
accident
conditions
-Thc program
must
include:
Training of personnel
2.
Procedures
for sampling
and
analysis
3.
l;rovisions for maintenance
of sampling
-;:~.nd analysis
equipment
RADIOIODINES AND PARTICULATES
REGULATORY REQUIREMENTS
Capability of sampling
postaccident
effluent
radioiodines
and
particulates
Sampling
and
analysis
dose
less
than
C11t.'8) 18
Pegulatory
guidance
does
not require
backup
Hegt1latory
guidance
does
not limit equipment
a!lo~.@ed
outage
time
f7AOIQIOOINE ANO PARTICULATES ANALYSIS
NUREG-0737 CAPABILITIES
NUBEG-0737
requirements
met
by midrange
(PE-32)
and
high range
(RX-40)
3 983
NRC inspection
report
acknowledged
use
of BE-32 for midrange
with understanding
that
Bl(-40 was
required
to meet
high range
k
I=mergency
procedures
to the
use
of the
correct
monitor for the
plant conditions
SEE'QRE /993 DESIGN UPGRADE
PLANT VENT TO
ATHOSPHERE
IIIGH RANCE
GAIIHA
RX
IIOAHAL RAttCE
I
TOO I ttE
SAN'LEA
AE
24
RE
29
RE
NORHAL RANCE
28A
PARTICULATE
E
68
IIICN RANCE
IODINE L PARf ICULATE
cO
SAHPLER
RE
NOAHAL RANCE
RE
IAA
NOBLE CAS
IWB
ITISCH
RE
HIO RANCE
52
TOO INE
RE
HIO RANCE
BLE CAS
AE 22
AE-IS
AE-58
RE-S9
OECAT
TANX VEIII
- IA EJECTOR
OISCHAACf.
HTOAOCEtl PUACEI
COttIHrtT EXCESS
PAfSSUAE RELIEf
COttTAINHENT
PURGE
EXHAUST
CE/Cw
EXHAUST
fttB EXHAUST
AUX,BLOC.
EXHAUST
II
RAQIOIODINES AND PARTICULATES
DRMS PROGRAM
Major upgrade
to
radiation
monitoring
capabi l It~J
8=placed
plant vent
rad
monitor skids
RE-14 noble
gas
BE-24 iodine
RE 28 particulate
)nstalled.new
high range
RE-87
high range
noble
gas
New high range
and particuiate
(iSP)
samplers
RF-87A
and
87B
Removed
BE-32
l8P
and RE-33
noble, gas
I
AFTER DESIGN CHANGE
~
4
PLANT VEIIT 'TO
ATHOSPHERE
IIIGH nAIIGE
cnoss
GAILHA
I.O To IET An/br
RE
NORHAL RANCE
RE
2B
, PARTICULATE
2BR
RE
NORHAI. RANCE
RE
f
Rf'<
teotNE
2iR
'ITA
HIGH RANGE
IOOINf. I PARTICULATE
SAILER
ttlcH nAHGE
)ODltIE R PARTICULATE
sAppLEA
RE
NOAHAL RANGE
RE
NOBLE CAS
IAA
HIGH RANCE
NOBLE. CAS
OI SCH
Af 22
RE-15AE-ISR'E-A]A
RE 448
RE
AE SB
GLS DECAY
IANX VENT
AIA EJECTOA
0 ISCIIAAGE
HTOAOCEN PURGE/
CONT@AT EXCESS
PAESSURE AELIff
CONTAINHENT
PURGE
EXHAUST
CE/Cw
EXHAUST
fHB EXHAUST
AUX.BLOC.
EXHAUST
- ':;.ADIQIQIINES AND PARTICULATES ANALYSIS
. PASS ECG DEVELOPMENT
lns'i:allation of
3 993
DBMS upgrade
required
R':-40
io be
taken
out for a short
period
Regulatory
guidance
did not limit
equipment
allowed
outage
time
(AOT)
developed
equipment
control guideline
(ECG)
program
to specify
AOTs for selected
non TS
eqUipment
30
day
AOT generally
provided for
post-accident
instrumentation
I=CG
i i.3
was
developed
for PASS
and
used
to
guide
i 993
design
upgrade
jH
EGG 111 REQUIREMENTS
Specifies
RE-32
as
principal method
Specifies
RX-40 and RE-24
as
alternates
RX-40 GDC-19
qualified
BE-24 not
GDC 19 qualified
requires
verification that
an
alternate
method
to RE-.32
is available
within 7 days
.--~oq~!it.e-. restoration
of RE-32
in 30 days
a~{t n
0
,=:AI3IOIOO!NES AND PARTICULATES ANALYSIS
CHRONOLOGY
2/28/93
During the
DBMS upgrade,
RE-32.and
RX-40
were
declared
and
reliance
placed
on alternate
RE-24.
3/4/93
PAl'viS panel
clearance
activities
completed
and RX-40 reenergized
{without power
5 days
16
l-lrs).
/5/9~
~>/Q/Q3
Functional
test
of RX-40 initially identified
high sample
flow.
BX-'40 reevaluated
and
flow found acceptable.
Declared
RX-40 operable
12
days).
II
I
RADIOIOOINES AND PARTICULATES
ROOT CAUSE ANALYSIS
EGG
l 3. 3
was
inaccurate;
RX-40 should
have
been
identified as
the
primary method
with
30-day
AOT.
In addition, RE-32
and RE-24
should
have
been
identified as
prudent
alternatives,
noting RE-24
did not meet
i-l"~-40 aciual
outage
time was
reasonable.
'AOIOIQOINES AND PARTICULATES ANALYSIS
CORRECTIVE ACTIONS
Completed
implementation
of DBMS upgrade
to enhance
capabilities
of overall system
EP RB-12
and
particulate
sampling
during
accidents)
revised
to include
use
of new radiation
monitors
6-3~!
and- ECG
11.1
revised
to reflect
nevr
configuration
and GDC-19
equipment
as
primary
dI:-.I-OHIE DESIGN UPGRADE
I;I'!'LUEHT TYPE
HOBINL
IIIORAHGE
IIIGII RAHGE
I!0!!LE GASES
RE14
ihtt
E 33
laE 2g
BAOIOIOOIIIES
[R
24
BE 3
ht small
[!IX 90
Grab
sam
er
Usefu
ran
e de ends
on
T .
I'JillT I CULATCS
depends
on Ts.
IX 10
Grab
sam
er
Usefu
ran
e kcgv4 to
RX
for
rad o odlnes,
depends
on Ts.
RX 32 33
Grab
sam hler
Useful range
keyed to RE 32/33
function, depends
on Ts.
I10'0'10'10'10
10
10'f
fLUtHI COHCL'HTRATIOH (pCI/cc)
0
.'of.U."f r ref>>;
flpll~ I@I
MONITOR RANQFS
MIOAAf4GC
IllCl 1 RhNCE
14
14B
ftft',0/'<fr
24 Z4ft
IV"!0'9D!fling
ffY 40
Crab
aacn
Ier
Useful ron
e de
nda an T~
fifar07 h tf
Crab
sam
ar
Ueatvl ron
a de
de an 'Tamo4
BL 2U 2tfA
~'1Ã lith
ftY, -tA
Ora& aom lar
Useful ron a de ends
an
Too
moo
n
i!I
II~TA 0 & b
I
U
1
t
d
d
T
}
I
}"
f'f- .- f0- ~
f0- a t0-
10-"
10-r
1 0-o
10=
1 Ow
10-s
10-z
10-1
10o
101
10m
10s
10
10o
Crn Vmr CONCntTmTfoff ( f1Cf/'cc)
= ~
'-4'QfOIGDINIES AND PARTICULATES ANALYSIS
SAFETY SIGNIFICANCE
8"-40
no~ used
for mitigation of design
basis
acclcl en ts
BX-40 i" only needed
for a worst case
accident
Ev('.n
in
a worst case
accident,
other
methods
and
equipment
are
available
to develop
protective
action
recommendations:
Ep R-2, release
of airborne
radioactive
materials
Emergency
assessment
and
response
system
(EARS)
RB-B, calculation
of release
rates
RB-
l 0, dose
calculations
and
projections
RB-7
and
RB-8, field-monitoring
ihip'-40 considered
12
days
(within 30-day
AOT)
Safety
significance
very low
7-ADIQIOOINI:- ANO PARTICULATES ANALYSIS
OVERVIEW
Actual outage
time for RX-40 was
reasonable
Equipment
control guidelines
did not accurately
ref!act primary
and
backup
equipment
designation
DBMS upgrade
and
procedural
corrective
actions
have
already
been
implemented
Safety
significance
very- low
HC <3ISSGI VED HYDROGEN ANALYSIS
NRC ISSUES
I ow availaoility of Unit
2 in-line monitor
No
for gas
chromatograph
(GC}
b:-"."I<up method
deletion
After GC method
deletion,
backup
methods
c)id not meet
GDC- 1 9 requirements
"./=ACTOR COOLANT OISSOLlfED HYOROGEN
ANAI')iBIS NUREG-0737 REQUIREMENTS
Capability
to sample
and
analyze
reactor
coolant
dissolved
within 3 hours3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br />
with less
than
5
REM wholebody
dose
to
any
i ndl vidual
lf in-.line monitoring
used,
backup
grab
sample
capability
must
be
provided
and
-d='monstrated
to meet
GDC- lg
'-';~ ~338 -. '('~/EQ HYDROGEN ANALYSlS
CHRONOLOGY
Original
Do"ign
I 987
':;.'/,
I /90
~I./9 1
8/92
></fQWp
I'l/9
Sentry
remote
grab
sample
GC primary
metliod.
Alternate
methods
are
grab
sample
from
panel
and
primary sample
system.
IO CFR
50.59
performed
for in-line monitor
design
change
In-line monitor installed
in Unit 2
and
Unit
1
as
enhancement
to improve reliability
of RCS
dissolved
and
containment
atmosphere
analysis.
ln-line monitors
added
to program
as
primary
method.
Training
and
procedures
in place.
Removed
GC for hydrogen
from procedures
as
Q bacl(up
Recurring
failures
of Unit 2 in-line monitor
RC DISSOLl/EO HYOROGEN
CHRONOLOGY SUMMARY
PGKE was
in non-conformance
with the
regulations
from the
time the
GC backup
was
not available
A written 60.59
was
not performed
in 8/92
when
the
GC
was
removed
as
the
backup.
However,
a safety
screen
was
performed
that
indicated
a written 50.69
was
not required.
I he
Unii 2 in-line monitor
had
low avai)ability
iiom 8/92
'o 2/93
I
~ ~ l I~I
~All1<+fi ~
eti i
el
ltllla-
alllII
swan.rem
UNIT 2 CEIL-1109
f!/!AI'NTI:-/VANCEACTIVlTIES 8/92-4/93
";;~/82
Replaced
Cell and
Performed
Electronic
Calibration
i 0/92
Replaced
Cell Twice
and
Electronic
Calibration
Performed.
(Vendor Consulted)
i I/92
El
ct~ onic Calibration
'i i/92
Meetings
with
PGB E Engineering
to Discuss
Cell
Replacement
I /93
2/9"-.
Replaced
Cell and
Performed
Electronic
Calibration
4/93
Replaced
Cell and
Performed
Electronic
Calibration
with Vendor Assistance
~!-i.fIOo )ViAINTENANCEACTIVITIES
5/83
Pi.ocedure
enhancements-
in progress
which
v!iii reduce
cell soak
time
and
improve
cell
avai1abi
lity
Recent
cel! performance
satisfactory
~C Qi.""SSC~L'/EO HYOROGEN ANALYSIS
PiOOT CAUSE
" ..=,C;neihod
deletion
lnadeq'uate
review of NUREG-0737
requirem'ents
Low availability of in-line monitor
RecI~rring in-line failures
due
to out of
alignment
in-line sensor
inlet and
sample
inlet probe.
inlet probe
also slightly bent.
0
".'I'~8C)L YEO HYOROGEN ANALYSIS
CPP)REC TIVE ACTIONS
i<!",;e
.",e;",;".o:
probe
installed
for in-line system
'3"-nsor piobe
alignment
tool is being
manufactured
( iquid coalescing
filter installed
to reduce
moisture
carryover
in
GC method.
Sl P 6- i~l
and
EP RB-15B revised. to reinstate
GC
mei:hod
as
backup
i'='rainin-i completed
on
GC method
r
Compr- hensive
review of PASS
GDC-19 requirements
in pi ogl ess
I-'",~L, iililfIARY REVIEW OF NVREG 0797
COMPLIANCE
i'I'AVi)=Tl- R-
l iC rndlonucl!des
P C diss olved
!lC chloride
lk(i oxy(pen
Cont .Inlllont ra( 10
nuclides
Containment
PRINCIPAL METHOD
grab
sample
PASS in-tine
analysis
remote
grab
sample
grab
sample
This parameter
is recommended.
Not required
by NUREG 0737.
uses
an in-line monitor
and
has
no GDC-19 qualified
backup.
grab
sample
ln-line monitors
Cel 82
5 83
BACKU P
Not
required
Remote
grab
sample
Not
required
Not
required
Not
required
Remote
grab
sample
,'=,C GIBSOi ~fED HYDROGEN ANALYSIS
SAFEST Y SIGNIFICANCE
i<lot used
fot
design
basis
accident
mitigation
Dissolved
was
intended
to check
for
a
bubble
following a postulated
severe
accident
Size
of bubble
unverifiable
by hydrogen
concentration
Other
noncondensibles
could
be present
(N2 from
noble
gases)
Olher, ystems
are
used
to perform the
same
function
including RVLIS, sub-cooled
margin monitor, incore
thermocouples,
and
pressurizer
level/pressure
t ".s pon" = characteristics
EP RB- i4
Core
damage
assessment
procedure,
does
t ot utilize dis" olved hydrogen
analysis
l-'iCS venting procedure
(EP FR-I.3) relies
on RVLIS
and
not
RC dissolved
measurements
0
QUOTE FROM NUREGfCR-4930
"REVIEW'F LIGHT VYATER REACTOR
REGUl ATORY REQUlREMENTS"
"t-lowevei., other
NRC regulations
establish
l Bqu ll 8 ments
fol:
(1)
A reactor
vessel
level indication
system
to detect
the presence
of a bubble
and
core
uncovery,
and
A head
vent system
to remove
noncondensible
gases
from the
high points
of the
reactor
coolant
system.
These
systems
adequately
remove
the potential
for noncondensible
gases
to interfere
with core
cooling.
The
"ample requirement
is redundant
with these
requirements."
.=,,r DISSQi VED HYDROGEN ANAIYSIS
SAFFTY SIGNIFICANCE (CONT.)
I-"I.oposed indu"try severe
accident
guidelines
v.fill not rely
on
RC dissolved
~!lRC and
industry
reviewing
requirements
a". marginal
to safety
(57
Federal
Register
55156,
November
24,
I 992)
-".a;"."=-!:~I,";!gniiicance very low
RG'JSSQLVEO HYOROGEN
SUMMARY
- -GS.E
divas
not
in full compliance
with the
r;=gula~:ions
requiring
a GDC-19
backup
l-)isioi y of PASS
enhancements
kllaintenance
problems
diligently pursued
Timely and
comprehensive
corrective
actions
i~iave n'.~"'s'een
taken
Sa~.ety,"'ignificance
very low